We present a novel approach intended to reduce user effort required to retrieve and/or revisit previously discovered information by exploiting web search and navigation history. In our approach, we collect streams of user actions during search and navigation sessions, identify individual user goals and construct and persistently store visual trees representing session history. We provide users with a History Map-a scrutable graph of semantic terms and web resources with full-text search capability over individual history entries, constructed by merging individual session history trees and the associated web resources. The Map semantically organizes a user's browsing history (with the help of the Delicious folksonomy) and enables him to quickly recall information distributed over several documents and/or sessions. We present experimental results of session identification and also evaluate our prototype over generic web pages and as well in conjunction with our personalized faceted semantic browser Factic with promising initial results.

With the proliferation of mobile devices, management of the growing user personal generated multimedia content is more demanding. Proper organization of this content requires manual metadata authoring, since automated or crowdsourcing approaches are inapplicable in case of personal content or content of a small social group (e.g. family). Recently, games with a purpose gained popularity in solving many human intelligence tasks, with main focus drawn onto resource metadata and semantics acquisition. Games with a purpose seem to have large potential for solving further problems, but they also face several design issues involving mainly the validation of human-created artifacts they provide. In this paper we analyze these issues and propose directions for overcoming them for the semantics acquisition domain. Furthermore, we propose a method for annotating and presenting personal multimedia content based on our previously developed game with a purpose, which also exploits the alternative artifact evaluation.